Omalizumab as a desensitizing agent and treatment in mastocytosis: a review of the literature and case report.

Patients with all forms of mastocytosis can experience urticaria, abdominal cramps, nausea, diarrhea, or hypotension due to release of mediators by mast cells. Patients with mastocytosis and Hymenoptera venom allergy can develop severe adverse reactions to Hymenoptera stings. In addition, patients with mastocytosis and on venom immunotherapy are at high risk for incomplete protection and fatal reactions. Recent literature has reported the use of omalizumab as an adjunctive treatment in patients with mastocytosis, used for both symptom improvement and to dampen adverse effects caused by venom immunotherapy. This article reviews the literature regarding omalizumab use in the treatment of mastocytosis and for protection against the adverse effects during venom immunotherapy. In addition, we report the case of a patient at high risk and with cutaneous mastocytosis, whose symptoms improved with concomitant administration of omalizumab and venom immunotherapy.